Engine Mounts

[wallyf]

Hi - I could really use some help. I have a 1GM10 Yanmar engine... that needs it's engine mounts replaced... Can anyone give me any pointers? I feel like I'm going in blind here as I have never done this before.
Many thanks,
Wally

[Boracay]

How much experience do you have with mechanical repairs?

Replacing engine mounts is likely going to be time consuming and a little tricky.

A good mechanic could probably do it in a couple of hours on a small engine like yours.

[Roy M]

The following few replys will show the sequence I used for my Yanmar 3GM30 FW. First, build a jig from plywood and 1" dowel (assuming that's your shaft size). Mount the engine mounts on the engine, with the adjustment thread in the middle position. Determine the position of the shaft jig (how far from the underside of the engine mount flange to the centerline of the shaft), and drill the holes (1") in the ply, then screw the ply to the base piece. Now, confirm that the shaft is in-line with the engine and precisely below the centerline of the engine. The Installation diagrams for the engine provide all this info, but it's easy to forget about the thickness of the plywood, etc.

Now, you are ready to do a trial fit on the existing engine bed logs. If the bed logs need to come in closer, epoxy and screw (or bolt), some 2 X 4 pieces where they are needed. Fit the jig again to determine if you need to raise or lower the bed logs to match up the shaft with the shaft coupling. You can attach the engine coupling to the dowel to get a very close fit. Be sure that you measure how far aft of the motor mounts the engine coupling will fit. If you are very brave, drill some starter holes for your engine mount lag screws or bolts. If you are anxious (as I was) skip this step, and do it later with the actual engine, removing the engine to install the mounts afterward.

Bolt the mounts onto the engine. Lower the engine onto the bed logs (this is the trickiest part, trying to work with heavy stuff in close quarters). Use lots of friends, chainhoists, whatever allows you to position carefully the engine onto the bedlogs. Slide the engine back or forth and sideways until the mounts rest securely on the bed logs. Using the engine coupling and shaft coupling, make sure the engine is in-line with the shaft. Mark the holes in the engine mount feet, pull the engine out and secure the mounts to the bed, then return the engine to its rightful position. You are in! And it will take more than a couple hours if this is your first engine, or the position of the engine bed logs is a challenge. Just take your time. I think the accompanying photos are self explanatory. Good Luck!

[Roy M]

For hoisting the engine, I just use the main halyard, then a chainhoist for the final positioning. I had to slide the engine into the engine room on a plank, raise it with the hoist, remove the plank, and position the engine.

[Roy M]

Good grief! I re-read your request, you didn't need all of this stuff. Oh well, sorry.

[dkall]

Our process, on a little larger engine. Pull off one engine mount / time. Take mount to body shop and have bead blasted. Prime and Paint. Replace the rubber foot for the mount. Put mount back on. Neutralize all the fittings, Use anti-sieze on all the nuts and bolts, tighten down. Move on to next mount.

Fair Winds.

[Chief Engineer]

Or.....you can raise the engine....remove the mounts one at a time (use Yanmar mounts) note the holes in the mounts are different (one round one oval) with old mount off....turn lower nut to the same level..install one at a time. Lower engine back into place...put mounting screws in....align engine....secure all nits bolts.

[wallyf]

Hi All - many thanks for your help!